Control of the data quality

Control of the data quality is carried out in each research in the following way: by control of the interview blank fill quality, execution of instructions, control of route sheets and closing statements by regional supervisors and the network manager; by spot check (up to 10%) of the conducted interviews over the phone or by supervisors’ (or by a third party) second visits; by logical control (or by control with the help of special programs) of the aggregate results; data re-weighing. Compliance with these standards as a result allows to obtain reliable, objective information.